FBI Director James Comey twice called the deadly Chattanooga shooting that killed four Marines and one sailor a "terror attack" during a press conference with NYPD commissioner Bill Bratton on Wednesday. Bratton and Comey spoke after addressing the NYPD Shield Conference in New York City.

"We've investigated Chattanooga as a terror attack from the beginning," Comey said. "The Chattanooga killer was inspired by a foreign terror organization. It's hard to entangle which particular source…there are lots of competing poisons out there."

That response came as Comey was asked to clarify an earlier statement in which he linked the root cause of the July 16 rampage by Muhammad Youssef Abdulazeez, a naturalized U.S. citizen who was born in Kuwait, to the recent Islamic terrorist attack in San Bernardino.

"San Bernardino, as with Chattanooga, another terror attack we've dealt with in recent times ..." Comey began the answer to a question about the Dec. 2 terror attack in California.

Abdulazeez, 24, was fatally shot by police after opening fire at a military recruiting center and then driving to a reserve center, where he killed five.

Officially classifying the Chattanooga attack as terror would make Abdulazeez's victims eligible for Purple Hearts.

During the five months since the Chattanooga attacks, law enforcement officials and the Obama administration have seemingly had some reluctance to label that act a terrorist deed.

Then-U.S. Attorney Bill Killian said Chattanooga was being investigated as an act of "domestic terrorism" during a news conference on the day of the shooting -- but he walked back that terminology moments later, saying the investigation would ultimately determine if the rampage was terrorism.

Killian resigned in November to join a national law firm. His last day was Dec. 5.

The following evening, during an address to the nation, President Obama took another step toward defining Chattanooga more clearly.

"As we've become better at preventing complex, multifaceted attacks like 9/11, terrorists turned to less complicated acts of violence like the mass shootings that are all too common in our society," Obama said. "It is this type of attack that we saw at Fort Hood in 2009. In Chattanooga earlier this year. And now in San Bernardino."

Further clarification could come soon as an updated statement on the attack was expected to come this week, an FBI spokeswoman for the Knoxville office told FoxNews.com on Wednesday.